This section provides background information related to the present disclosure which is not necessarily prior art.
A drill guide can be used by a surgeon to direct a drill bit to bone at a surgical site. The drill bit can be inserted through a bore defined by the guide, and then rotated with a drill to form a bone hole at the site. A suture anchor can be inserted through the bore of the same drill guide using an insertion tool, and implanted in the bone hole in order to, for example, anchor tissue at the surgical site. The guide need not be moved after the bone hole is formed, and thus insertion of the anchor in the bone hole is facilitated and made more accurate because the guide is already aligned with the hole.
The drill bit often has an outer diameter that is smaller than an outer diameter or width of the anchor. To accommodate the anchor, the bore of the guide has an inner diameter that is greater than the outer diameter of the drill bit, which may not be optimal for drilling. Because the diameter of the bore is greater than the outer diameter of the drill bit, the guide will not be able to fully constrain the drill bit, which may result in the bone hole being drilled off-center from the guide. The guide thus may not accurately align with the bone hole, which may result in the anchor being damaged during insertion or missing the hole completely. This issue is exacerbated when the guide tube is curved because the drill may be angled away from the bend and press against an edge of the guide, which may damage the drill bit and/or make it difficult to form the bone hole exactly at an intended location.